CloudFront: Cost estimate

Question

Have to come up with a proposal to use Amazon S3 with CloudFront as CDN. One of the important thing is to do a cost estimate. I read over AWS website and forums, used their calculator, but couldn't come to a conclusion with the final number (approx) that I will be confident of. Honestly, I got confused between terms like "Data Transfer Out", "GET and Other Requests" and whether I need to fill in the details both at Amazon S3 and Amazon CloudFront and then do a sum total.

So need help here to estimate my monthly bill.

• I will be using S3 to store files (mostly images)
• I will be configuring cloud front with my S3 bucket to deliver the content.

• Most of the client base (almost 95%) is in US.

• Average file size: 500KB

• Average number of files stored on S3 monthly: 80000 (80K)
• Approx number of total users requesting for the file monthly or approx number of total requests to fetch the file from CloudFront: 30 Millions monthly
• There will be some invalidation requests per month (lets say 1000)

Would be great if I can get more understanding as to how my monthly bill will be calculated and what approximately it will be.

Also, with the above data and estimates, any approx on how much the monthly bill, if I use Akamai or Rackspace.

Solution 1

I'll throw another number into the ring.

Using http://calculator.s3.amazonaws.com/calc5.html

CloudFront
data transfer out 0.5MB x 30 million = ~15,000GB

Average size 500kb

1000 invalidation requests

95% US

S3
Storage 80K x 0.5MB 4GB

requests 30million

My initial result is $1,413. As @user2240751 noted, a factor of safety of 2 isn't unreasonable, so that's in the $1,500 - $3,000/month range.

I'm used to working with smaller numbers, but the final amount is always more than you might expect because of extra requests and data transfer.

Corrections or suggestions for improvements welcome!

Good luck

Solution 2

The S3 put and get request fields (in your case) should be restricted to the number of times you are likely to call / update the files in S3 from your application only.

To calculate the Cloudfront service costs, you should work out the rough outbound bandwidth of your page load (number of objects served from cloudfront per page - then double it - to give yourself some headroom), and fill in the rest of the fields.

Rough calc. 500GB data out (guess) 500k average object size 1000 invalidation requests 95% to US based edge location 5% to Europe based edge location

Comes in at $60.80 + your S3 costs.

Solution 3

I think the maths here is wrong 0.5MB * 30,000,000 is 14503GB NOT 1500GB - thats a factor of 10 out unless I'm missing something

Which means your monthly costs are going to be around $2000 not $200

Comments

[user1270392]

Thanks for helping me out on the estimate and explaining how costing for s3 works!

[David Taiaroa]

@jkchu, thanks for pointing out the mistake in my initial post!